Search

Abstract: Recently, much attention has been paid by consumers toward natural bioactive compounds as functional ingredients in nutraceuticals. Marine algae are considered as valuable sources of structurally diverse bioactive compounds. Marine algae are rich in sulfated polysaccharides (SPs) such as carrageenans in red algae, fucoidans in brown algae and ulvans in green algae. These SPs exhibit many health beneficial nutraceutical effects such as antioxidant, anti-allergic, anti-human immunodeficiency virus, anticancer and anticoagulant activities. Therefore, marine algae derived SPs have great potential to be further developed as medicinal food products or nutraceuticals in the food industry. This contribution presents an overview of nutraceutical effects and potential health benefits of SPs derived from marine algae. [Copyright &y& Elsevier]

Abstract: Chitooligosaccharide (COS), a derivative of chitosan, can be produced by either chemical or enzymatic hydrolysis. Looking back through past research, several technological approaches have been taken to prepare COSs, and enzymatic approaches are favorable due to their environmentally friendly methods, safety, and a lack of toxicity. Similar to chitosan, COSs can also be considered potential nutraceuticals due to their versatile biological activities, water-soluble properties, and absorption properties in the intestine. Therefore, this chapter provides certain methods for the preparation of COSs and addresses their biological properties such as antihypertensive, antioxidant, antitumor, antimicrobial, and other select biological activities. [Copyright &y& Elsevier]

Abstract: Sponges are considered as the chemical factory in marine environment because of its immense production of chemically diverse compounds. Other than the chemical diversity, these compounds possess remarkable bioactivities. This great potential has aroused applications of sponge-derived compounds as therapeutics and at present, a number of promising compounds are in clinical and preclinical trials. Recently, nutraceuticals have received considerable interest among the health conscious community because of its multiple therapeutic effects. Natural health-promoting substances gain continuous popularity as nutraceuticals due to its reduced risk of side effects. This overview discusses the potentials of marine sponge-derived bioactivities as natural health-promoting compounds. [Copyright &y& Elsevier]

Abstract: Chitosan, the most abundant marine mucopolysaccharide, is derived from chitin by alkaline deacetylation, and possesses versatile biological properties such as biocompatibility, biodegradability, and a non-toxic nature. Due to these characteristics, considerable attention has been given to its industrial applications in the food, pharmaceutical, agricultural, and environmental industries. Currently, chitosan can be considered as a potential marine nutraceutical because its remarkable biological activities have been investigated and reported, in order to exploit its nutraceutical properties. This chapter, therefore, reviews the biological activities of chitosan including antioxidant, hypocholesterolemic, antimicrobial, and anti-inflammatory activities, as well as its mode of action in each activity. [Copyright &y& Elsevier]

Abstract: The importance of marine algae as sources of functional ingredients has been well recognized due to their valuable health beneficial effects. Therefore, isolation and investigation of novel ingredients with biological activities from marine algae have attracted a great deal of attention. Among functional ingredients identified from marine algae, natural pigments (NPs) have received particular attention. These NPs exhibit various beneficial biological activities such as antioxidant, anticancer, anti-inflammatory, anti-obesity, anti-angiogenic and neuroprotective activities. This contribution focuses on biological activities of marine algae-derived NPs and emphasizing their potential applications in foods as well as pharmaceuticals areas. [Copyright &y& Elsevier]

Abstract: Gallic acid-grafted-chitosans (GA-g-chitosans) with four different grafting ratios were prepared by a free radical-induced grafting reaction in order to improve antioxidant and water-solubility. To verify the synthesis of GA-g-chitosans, 1H NMR and thin layer chromatography were employed, and the results revealed that GA was grafted onto the chitosan. The antioxidant properties of the GA-g-chitosans were evaluated using several in vitro models. GA-g-chitosan (I), which has the highest GA content, showed 92.26% scavenging activity against 2,2-diphenyl-1-picrylhydrazyl and 93.15% hydrogen peroxide scavenging activity at 50μg/mL. GA-g-chitosan (I) was also showed higher reducing power compared to others. All GA-g-chitosans showed improved antioxidant capacities compared to plain chitosan treated in the same conditions without gallic acid grafting. Furthermore, the GA-g-chitosans also exhibited good cytocompatibility and effectively inhibited the formation of intracellular reactive oxygen species (ROS) in time- and dose-dependent manner in RAW264.7 macrophages. [ABSTRACT FROM AUTHOR]

Abstract: Chitosans with different degree of deacetylation were prepared from crab shell chitin in the presence of alkali. Aminoderivatized chitosan derivatives were prepared in addition of amino functional groups at a hydroxyl site in the chitosan backbone. Six kinds of aminoderivatized chitosan such as aminoethyl-chitosan (AEC90), dimethylaminoethyl-chitosan (DMAEC90), and diethylaminoethyl-chitosan (DEAEC90), which were prepared from 90% deacetylated chitosan, and AEC50, DMAEC50 and DEAEC50, which were prepared from 50% deacetylated chitosan, were prepared and their reactive oxygen species (ROS) scavenging activities were investigated against hydroxyl radical, superoxide anion radical and hydrogen peroxide. The electron spin resonance (ESR) spectrum revealed that AEC90 showed the highest scavenging effects against hydroxyl and superoxide anion radical, the effects were 91.67% and 65.34% at 0.25 and 5mg/mL, respectively. For hydrogen peroxide scavenging effect, DEAEC90 exhibited the strongest activity. These results suggest that the scavenging effect depends on their degree of deacetylation and substituted group. [Copyright &y& Elsevier]

Abstract: Novel water-soluble chitin derivative was prepared by chemical modification to evaluate antioxidant activities by free radical scavenging potential using electron spin resonance spin trapping technique. Aminoethyl-chitin (AEC) exhibited free radical scavenging activities against 1,1-diphenyl-2-picrylhydrazyl (DPPH), hydroxyl, superoxide, and peroxyl radicals. AEC quenched DPPH and peroxyl radical over 55% and 59% at 4mg/mL, and also suppressed superoixde radical over 58% at 2mg/mL. Especially, AEC was more active against hydroxyl radical, and scavenging ratio was 92.2% at 0.12mg/mL. These results suggested that free amino group in the –CH2CH2NH2 plays an important role in the free radical scavenging activity. In addition, cytotoxic effect of AEC was assessed using human lung fibroblast (MRC-5) cell line, and AEC showed less toxic against MRC-5. [Copyright &y& Elsevier]

Abstract: The aim of this study is to investigate the inhibitory effects of aminoethyl-chitooligosaccharides (AE-COS) on oxidative stress in mouse macrophages (RAW 264.7 cells). The inhibitory effects of AE-COS on DNA and protein oxidation were studied in RAW 264.7 cells. Furthermore, free radical scavenging effect of AE-COS were determined in RAW264.7 cells by 2′,7′-dichlorofluorescein (DCF) intensity and intracellular glutathione (GSH) level. AE-COS also inhibited myeloperoxidase (MPO) activity in human myeloid cells (HL-60). These results suggest that AE-COS acts as a potential free radical scavenger in RAW 264.7 cells. [Copyright &y& Elsevier]

Abstract: The aim of this research is to identify the cellular antioxidant effects of chitin oligosaccharides (NA-COS; M w 229.21–593.12Da) produced by acidic hydrolysis of crab chitin. The inhibitory effect of NA-COS on myeloperoxidase (MPO) activity in human myeloid cells (HL-60) and oxidation of DNA and protein in mouse macrophages (Raw 264.7) were identified. Furthermore, their direct radical scavenging effect by 2′,7′-dichlorofluorescein (DCF) intensity and intracellular glutathione (GSH) level were significantly increased in a time dependent manner, respectively. These results suggest that NA-COS act as a potent antioxidant in live cells. [Copyright &y& Elsevier]

Abstract: Scavenging activity of hydroxyethyl chitosan sulfate (HCS) against 2,2-diphenyl-1-picrylhydrazyl (DPPH), hydroxyl and carbon-centered radical species were studied using electron spin resonance (ESR) spectroscopy. In addition, its antioxidant activity to retard lipid peroxidation was also evaluated in a linoleic acid model system. HCS could scavenge DPPH (33.78%, 2.5mg/mL) and carbon-centered radicals (67.74%, 0.25mg/mL) effectively. However, chitosan sulfate did not exhibit any scavenging activity against hydroxyl radicals, but increased its generation. This was different from the published literature and was presumed due to the loss of chelating ability on Fe2+. This assumption could further confirm from the results obtained for Fe2+-ferrozine method that upon sulfation chitooligosaccharides lost its chelation properties. Therefore, HCS can be identified as antioxidant that effectively scavenges carbon centered radicals to retard lipid peroxidation. [Copyright &y& Elsevier]

In this study, gallic acid-conjugated chitooligosaccharides (gallate-COS) was evaluated for its enhancing capabilities in free radical scavenging and anti-inflammatory activities in human lung epithelial A549 cells. It was found that gallate-COS possesses significantly high DPPH radical scavenging activity and protective effect against H 2 O 2 -induced DNA damage. Likewise, gallate-COS decreased the production of intracellular reactive oxygen species in H 2 O 2 -stimulated A549 cells. Moreover, the suppressive effects of gallate-COS on COX-2 expression and PGE 2 production from LPS-stimulated A549 cells were evidenced. Finally, the productions of cytokines including IL-8 and TNF-α were also inhibited by gallate-COS in a dose-dependent manner. Collectively, these results suggest that gallate-COS could be used as a functional ingredient with potent antioxidant and anti-inflammatory benefits. [ABSTRACT FROM AUTHOR]

Unregulated activation of microglia is the major cause of neuronal degeneration in Alzheimer’s and Parkinson’s diseases. Excessive reactive oxygen species (ROS) generation is a common risk factor for chronic diseases, including neurodegeneration. In this study, N -acetyl chitooligomers (NA-COS, below 1 and 1–3 kDa) were produced from crab chitin using an ultrafiltration membrane system and investigated for their capabilities against H 2 O 2 -induced oxidative stress in murine microglia (BV-2 cells). NA-COS significantly decreased the oxidation of DNA by diminishing the intracellular ROS production. Furthermore, NA-COS upregulated the protein and gene expressions of antioxidant enzymes (superoxide dismutase and glutathione), thereby enhancing the intracellular antioxidant. Notably, NA-COS inhibit NF-κB activation by blocking degradation of the inhibitor of kappaB-alpha (IκB-α) and translocation of nuclear factor NF-κB (p65 and p50). Collectively, NA-COS could be potential agents for the prevention of neurodegenerative diseases. [ABSTRACT FROM AUTHOR]

Chitosan is a natural nontoxic biopolymer produced by alkaline deacetylation of chitin. Chitin and chitosan are insoluble in water as well as most organic solvents. Chito-oligomers (COS), depolymerized products of chitosan, has received much attention in biomedical, food, pharmaceutical, agricultural and environmental industries due to their biocompatible, biodegradable, non-toxic and non-allergenic natures. Chitosan and its derivatives have been shown to possess diverse biological activities, including antioxidant, anti-hypertensive, anti-coagulant, anti-diabetic, anti-obesity, anti-allergic, anti-inflammatory, anti-microbial, anti-cancer, neuroprotective and matrix metalloproteinases inhibitory effects. Thus, this overview mainly focuses on biological effects of chitosan and its derivatives as well as presents their potential applications as ingredients in functional foods and nutraceuticals for the prevention or treatment of chronic diseases. [ABSTRACT FROM AUTHOR]

Highlights: [•] Tyrosol dose and time dependently supresses MPP+-induced cytotoxicity in CATH.a neuron cells. [•] MPP+ induced mitochondrial dysfunction and ATP depletion was significantly attenuated by tyrosol. [•] Tyrosol treatment upregulated the anti-oxidative enzymes in neurone cells. [•] Tyrosol exerts a neuroprotective activity most probably via Akt signalling pathway. [ABSTRACT FROM AUTHOR]

Abstract: Marine organisms have been recognized as rich sources of bioactive compounds with valuable nutraceutical and pharmaceutical potentials. Recently, marine bioactive peptides have gained much attention because of their numerous health beneficial effects. Notably, these peptides exhibit various biological activities such as antioxidant, anti-hypertensive, anti-human immunodeficiency virus, anti-proliferative, anticoagulant, calcium-binding, anti-obesity and anti-diabetic activities. This review mainly presents biological activities of peptides from marine organisms and emphasizing their potential applications in foods as well as pharmaceutical areas. [Copyright &y& Elsevier]

Abstract: Seafood processing by-product, Pacific cod (Gadus macrocephalus) skin, was utilised to purify an active peptide with ACE inhibitory and antioxidant activities. Gelatin was extracted from the skin and it was hydrolysed with gastrointestinal endopeptidases (pepsin, trypsin and α-chymotrypsin). Assay-guided purification of the hydrolysate resulted in an active peptide, Leu-Leu-Met-Leu-Asp-Asn-Asp-Leu-Pro-Pro (1301Da). The peptide showed potent non-competitive ACE inhibition (IC 50 =35.7μM) and effectively protects cellular macromolecules from reactive oxygen species (ROS) mediated damage. The peptide significantly reduced the oxidation levels of membrane lipids, proteins and DNA in RAW264.7 cells by effectively scavenging the intracellular ROS. Moreover, it was found that the peptide treatment upregulated the m-RNA expression of cellular antioxidative enzymes (superoxide dismutase, glutathione and catalase) and thereby enhanced the intracellular antioxidant mechanisms. These findings suggest that Pacific cod skin could be effectively bioconverted to produce a bioactive peptide, which could be used as a functional food ingredient to control ACE activity and oxidative stress. [Copyright &y& Elsevier]

Abstract: The aim of this study was to investigate the antioxidant and anti-inflammatory activities of aminoethyl-chitooligosaccharides (AE-COS) in murine microglial cells (BV-2). At the high concentration of 100μg/ml, the inhibition of reactive oxygen species, DNA, protein and lipid oxidation were determined in BV-2 cells, at the rates of 77%, 80%, 85% and 85%, respectively. Furthermore, AE-COS was studied for its capabilities against lipopolysaccharide-induced inflammatory responses in BV-2 cells. It was found that AE-COS reduced the level of nitric oxide (NO) and prostaglandin E2 production by diminishing the expression of inducible NO synthase and cyclooxygenase-2 without significant cytotoxicity. Moreover, the inhibitory activities of AE-COS on generation of tumor necrosis factor-alpha and interleukin-1beta were performed. Collectively, these results indicate that AE-COS possess potential antioxidant and anti-inflammatory activities in brain microglia, and could be a useful therapeutic agent for the treatment of neuroinflammatory diseases. [Copyright &y& Elsevier]

Abstract: In this research, a novel derivative of chitooligosaccharides (COS) was synthesized by covalently linking gallic acid and COS (gallate-COS) via carbodiimide to improve cellular antioxidant activity. The direct intracellular radical scavenging effect of gallate-COS by 2′,7′-dichlorofluorescin diacetate (DCFH-DA) method, and the inhibition of oxidation of cellular macromolecules, such as DNA, protein and lipid in mouse macrophages (RAW264.7 cells) were determined. Furthermore, with the treatment of gallate-COS, the expression levels of antioxidant enzymes such as superoxide dismutase (SOD) and glutathione (GSH) were significantly increased according to reverse transcription polymerase chain reaction (RT-PCR) and Western blot analysis. In addition, gallate-COS decreased reactive oxygen species induced activation of the nuclear transcription factor (NF-κB). Collectively, these results suggest that gallate-COS can be used as a potential natural compound-based antioxidant in the functional food and pharmaceutical industries. [Copyright &y& Elsevier]

Abstract: Two new peptides derived from seaweed pipefish Syngnathus schlegeli, SPP-1(QLGNLGV) and SPP-2 (SVMPVVA) were assessed for their ability to prevent hydrogen peroxide induced oxidative stress in human dermal fibroblasts (HDFs). Both peptides showed a significant hydroxyl radical scavenging activity when tested by ESR technique. And also the peptides effectively suppressed the hydrogen peroxide induced ROS production and DNA damage in HDF cells. Furthermore the two peptides increase the protein expression levels of intracellular antioxidant enzymes SOD1, GSH and catalase in hydrogen peroxide stressed HDF cells. At the cellular signaling level, SPPs block the NF-κB activation which may lead to the reduction of oxidative stress mediated damage of HDF cells. These finding indicate the potential antioxidant effects of SPPs as response to H2O2 stimulation. [Copyright &y& Elsevier]

Abstract: Antioxidative and matrix metalloproteinase (MMP) inhibitory effects of methanolic extract from Sargassum thunbergii were investigated in HT1080 cells. This extract suppressed the electron spin resonance (ESR) signal intensity on generation of 1,1-diphenyl-2-picrylhydrazyl (DPPH) radicals and intracellular reactive oxygen species (ROS) formation by 2′,7′-dichlorofluorescin diacetate (DCFH-DA) method. Also, treatment with this extract inhibited radical simulated oxidation of membrane lipids and proteins in a dose-dependent manner. These results revealed that S. thunbergii extract has excellent scavenging abilities in ROS-induced damage. Moreover, this extract led to the reduction of the expression levels of MMP-2 and -9 in gelatin zymography, reverse transcription polymerase chain reaction (RT-PCR) and Western bolt analysis. Systematic separation by diverse chromatographic methods led to the isolation of sargahydroquinoic acid and sargachromanols (1–3). Polyunsaturated fatty acids were identified by gas chromatographic analysis. Therefore, S. thunbergii can be developed as therapeutic potential antioxidant and MMP inhibitor, closely related to ROS, which can be traceable to sargahydroquinoic acid, sargachromanols, and polyunsaturated fatty acids contained in S. thunbergii. [Copyright &y& Elsevier]

Abstract: Protein derived from the rotifer Brachionus rotundiformis was hydrolyzed using different proteases (Alcalase, α-chymotrypsin, Neutrase, papain, pepsin and trypsin) for production of antioxidant peptide. Antioxidant activities of hydrolysates were evaluated using DPPH radical scavenging activity. Peptic hydrolysate exhibited the highest antioxidative activity compared to other hydrolysates. To identify antioxidant peptides, peptic hydrolysate was purified using consecutive chromatographic methods, and antioxidant peptides were identified to be Leu-Leu-Gly-Pro-Gly-Leu-Thr-Asn-His-Ala (1076Da), and Asp-Leu-Gly-Leu-Gly-Leu-Pro-Gly-Ala-His (1033Da) by Q-TOF ESI mass spectroscopy. EC50 values of purified peptides were 189.8 and 167.7μM, respectively. Antioxidant activities of peptides purified from the rotifer protein hydrolysate were evaluated, with results showing that peptides significantly quenched free radicals. [Copyright &y& Elsevier]

Abstract: Matrix metalloproteinases (MMPs), a key component in photoaging of the skin due to exposure to ultraviolet A, appear to be increased by UV-irradiation-associated generation of reactive oxygen species (ROS). In this study, the alga Corallina pilulifera methanol (CPM) extract has been shown to exert a potent antioxidant activity and protective effect on UVA-induced oxidative stress of human dermal fibroblast (HDF) cell. Antioxidant evaluated by various antioxidant assays. These include reducing power, total antioxidant, DPPH radical scavenging, hydroxyl radical scavenging and protective effect on DNA damage caused by hydroxyl radicals generated. Further, the ROS level was detected using a fluorescence probe, 2′,7′-dichlorofluorescein diacetate (DCFH-DA), which could be converted to highly fluorescent dichlorofluorescein (DCF) with the presence of intracellular ROS on HT-1080 cells. Those various antioxidant activities were compared to standard antioxidants such as α-tocopherol. In addition, the in vitro activities of MMP-2 and MMP-9 in HDF cell were inhibited by C. pilulifera methanol extract dose dependently by using gelatin zymography method. The results obtained in the present study suggested that the C. pilulifera methanol extract may be a potential source of natural anti-photoaging. [Copyright &y& Elsevier]

Abstract: To utilize fish processing waste, tuna backbone protein was hydrolyzed using different proteases (alcalase, α-chymotrypsin, neutrase, papain, pepsin and trypsin) for production of antioxidant peptide. Antioxidant activities of hydrolysates were evaluated using lipid peroxidation inhibition assay and direct free radical scavenging activity by using electron spin resonance (ESR) spectrometer. Among hydrolysates, peptic hydrolysate exhibited the highest antioxidant activity compared to other hydrolysates. To identify antioxidant peptide, peptic hydrolysate was purified using consecutive chromatographic methods, and the antioxidant peptide was identified to be VKAGFAWTANQQLS (1519Da) by Q-TOF ESI mass spectroscopy. The antioxidant activities of antioxidant peptide from tuna backbone protein (APTBP) was evaluated, and the results show that APTBP significantly inhibited lipid peroxidation in linoleic acid emulsion system and also quenched free radicals (DPPH, hydroxyl and superoxide) in a dose-dependent manner. Moreover, APTBP did not show any cytotoxic effect against MRC-5 and ECV304 cell lines. [Copyright &y& Elsevier]

Abstract: The objective of this study was to identify the cellular antioxidant effects of carboxylated chitooligosaccharides (CCOS), a chemically modified derivative of chitooligosaccharides (COS), by assessing oxidation inhibition potential on cellular biomolecules such as lipids, proteins, and direct scavenging of reactive oxygen species (ROS). Radical-mediated oxidation of cell membrane lipids and proteins was dose-dependently inhibited by CCOS, assessed by amount of lipid hydroperoxides and carbonyl carbon content in mouse macrophages, RAW264.7 cells. Further, CCOS inhibited myeloperoxidase (MPO) activity in human myeloid cells (HL60) suggesting indirect possibility of inhibiting generation of reactive oxygen species (ROS) such as superoxide radicals, H2O2 and HOCl. Direct radical scavenging studies carried out with DCFH-DA fluorescence probe concluded that CCOS can act as a potent radical scavenger in cells. [Copyright &y& Elsevier]

Abstract: Low molecular weight peptides obtained from ultrafiltration (UF) of giant squid (Dosidicus gigas) muscle protein were studied for their antioxidative effects in different in vitro oxidative systems. The most potent two peptides, Asn-Ala-Asp-Phe-Gly-Leu-Asn-Gly-Leu-Glu-Gly-Leu-Ala (1307 Da) and Asn-Gly-Leu-Glu-Gly-Leu-Lys (747 Da), exhibited their antioxidant potential to act as chain-breaking antioxidants by inhibiting radical-mediated peroxidation of linoleic acid, and their activities were closer to highly active synthetic antioxidant, butylated hydroxytoluene. Addition of these peptides could enhance the viability of cytotoxic embryonic lung fibroblasts significantly (P<.05) at a low concentration of 50 μg/ml, and it was presumed due to the suppression of radical-induced oxidation of membrane lipids. Electron spin trapping studies revealed that the peptides were potent scavengers of free radicals in the order of carbon-centered (IC50 396.04 and 304.67 μM), hydroxyl (IC50 497.32 and 428.54 μM) and superoxide radicals (IC50 669.34 and 573.83 μM). Even though the exact molecular mechanism for scavenging of free radicals was unclear, unusually high hydrophobic amino acid composition (more than 75%) of giant squid muscle peptides was presumed to be involved in the observed activities. [Copyright &y& Elsevier]

Abstract: Fermented marine blue mussel (Mytilus edulis) derived peptides were purified using ion exchange, gel filtration and high performance liquid chromatographic techniques to identify a potent radical scavenging activity. The hepta-peptide sequence, HFGBPFH (MW 962 kDa) was found to be highly effective for radical scavenging and was named as mussel derived radical scavenging peptide (MRSP). Under the assay conditions, MRSP could scavenge superoxide (98%), hydroxyl (96%), carbon-centered (91%) and DPPH radicals (72%) at 200 μg/ml concentration and the respective IC50 values were found to be 21, 34, 52 and 96 μM. In addition, MRSP exhibited a strong lipid peroxidation inhibition at 54 μM concentration and it was higher than α-tocopherol. Further, it exhibited a 95% higher Fe2+ chelating effect than citrate. Moreover, MRSP could enhance the viability of oxidation induced cultured human cells by 76% following 75 μg/ml of treatment. Therefore, these results identified MRSP as a potent natural antioxidant, which performs its activity via different mechanism of actions. [Copyright &y& Elsevier]